*
  margin: 0
  padding: 0
body
  //背景图片
  background-image: url("../images/bg.jpeg")
  //背景定位
  background-attachment :fixed
  background-repeat :no-repeat
  background-position :center center
  background-size :cover
  background-color :#fff
  font :14px 'microsoft yehei'
  font-weight :300